What is Magento 2 index

Due to the sophisticated architecture, Magento gathers a lot of merchant’s data, e.g.: catalog info, prices, users, stores, in many database tables. To optimize the Magento 2 frontend performance the most important information is stored into special tables using indexers that gathering the data. You need to keep the indexes up-to-date to show actual data on the storefront. 

When Magento 2 reindex is required

In Magento 2 reindex is required for these 8 indexers when any changes are made:

E.g.: when updating a product price the data should be reindexed to be correctly displayed on the frontend. The indexation sufficiently reduces time spent on calculating a final order price including cart price rules, bundle pricing, discounts, tier pricing, etc. 

1. Category products;
2. Product categories;
3. Product price;
4. Product entity attribute value;
5. Stock;
6. Catalog rule product;
7. Catalog product rule;
8. Catalog search.

In older Magento versions indexation is dependent on the indexer.php file placed under the shell folder. In Magento 2 it’s managed by the bin/magento instead.

How to reindex Magento 2?

To reindex indexes in Magento 2 you can use several ways: reindex via a cron job and use manual reindex from the admin panel.

Reindex via a cron job

Reindex Magento 2 via a cron job is very convenient way. In this case reindexing runs every minute (you can set an appropriate period) eliminating the necessity to manage the process manually . To configure a cron job correctly follow the guide.

Manual reindex from the Admin Panel

You can use Magento 2 manual reindex via the command line:

• Log in to your Magento server admin panel as the file owner;
• Use the next option:php bin\magento indexer:reindex where [indexer] is a space-separated list of indexers;
• The option is suitable for reindexing all the store: php bin\magento indexer:reindex. In this case, you’ll see the corresponding results:

However, reindexing of all indexers can take long, therefore, you’d better manage a cron job for the issue.

• If you  want to see the list of all indexers, type in: php bin\magento indexer:info. Here you can find the name of a definite indexer, which is to be further reindexed through the command: php bin\magento indexer:reindex indexer_name (the name of a desired indexer is applied to the ‘_name’ part). 

Helpful hint: If you need a complex solution to prevent your M2 store from lags due to the too long loading, try out this Reindex from Admin. Having installed it, you'll reindex data in a click right from the admin panel, automate the reindexing, check the reindex process in a live regime.